Fuel Pump Electrical Circuit

When the ignition switch is in the ON position, before engaging the starter, the control module energizes the fuel pump relay for 2 seconds causing the fuel pump to pressurize the fuel system. If the control module does not receive the ignition reference pulses, with the engine cranking or running, within 2 seconds, the control module shuts OFF the fuel pump relay, causing the fuel pump to stop. The control module will also turn ON the fuel pump for 2 seconds when the ignition switch is turned to the OFF position.